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United States Patent | 5,203,233 |
Hattori ,   et al. | April 20, 1993 |
A hydraulic control apparatus for controlling a belt-and-pulley type continuously variable transmission of a motor vehicle having an engine, which transmission includes a pair of hydraulic actuators one of which receives a belt tensioning pressure for controlling a tension of a transmission belt. The hydraulic control apparatus includes an engine-output detecting valve for generating an engine output pressure indicative of a currently required output of the engine, a solenoid-operated valve for regulating a modified engine output pressure based on the engine output pressure generated by the engine-output detecting valve, and a pressure regulating valve for regulating the belt tensioning pressure based on at least the modified output pressure. The modified engine output pressure is obtained so that the belt tensioning pressure is controlled to an optimum level.
Inventors: | Hattori; Yuji (Susono, JP); Soga; Yoshinobu (Susono, JP); Sugaya; Masami (Susono, JP); Kato; Nobuyuki (Susono, JP) |
Assignee: | Toyota Jidosha Kabushiki Kaisha (Toyota, JP) |
Appl. No.: | 805058 |
Filed: | December 11, 1991 |
Dec 28, 1990[JP] | 2-416144 |
Current U.S. Class: | 477/45; 474/18; 474/28; 474/70; 474/101 |
Intern'l Class: | B60K 041/14 |
Field of Search: | 74/865,866,867,868 364/424.1 474/18,28,70,101 |
4488456 | Dec., 1984 | Taga et al. | 74/866. |
4638689 | Jan., 1987 | Sakai | 74/867. |
4669336 | Jun., 1987 | Okada et al. | 74/868. |
4747327 | May., 1988 | Itoh et al. | 74/868. |
4772249 | Sep., 1988 | Kuono et al. | 74/868. |
4881925 | Nov., 1989 | Hattori | 74/865. |
4955260 | Sep., 1990 | Oshidari | 74/868. |
Foreign Patent Documents | |||
57-161360 | Apr., 1982 | JP. |